Revert of Create our own blink_heap run_all_tests target to avoid piggy-backing on wtf's. (https://codereview.chromium.org/139293003/)

Reason for revert:
Failing blink_heap_unittests on MAC. 

Original issue's description:
> Trying this patch again. From what we can tell it was a glitch in the MAC WebKit builder since it seemed to recover before the change was reverted.
> 
> Create our own blink_heap run_all_tests target to avoid piggy-backing on wtf's.
> 
> We used to use wtf's run_all_tests target to run out blink heap unittests. That causes a problem when we want to initialize our heap since we cannot call Heap::init/shutdown from wtf's RunAllTests since it cannot/should not depend on blink heap.
> 
> R=ager@chromium.org, erik.corry@gmail.com, haraken@chromium.org, vegorov@chromium.org, zerny@chromium.org
> BUG=
> 
> Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=165205

TBR=ager@chromium.org,erik.corry@gmail.com,haraken@chromium.org,vegorov@chromium.org,zerny@chromium.org,alexeif@chromium.org
NOTREECHECKS=true
NOTRY=true
BUG=

Review URL: https://codereview.chromium.org/135853018

git-svn-id: svn://svn.chromium.org/blink/trunk@165207 bbb929c8-8fbe-4397-9dbb-9b2b20218538